282 Responses to “Unforced variations: Aug 2015”

@BPL 222: Point taken that not all land will suffer drought, because some will flood. But I thought that F represented the fraction of agricultural land that was in drought. Unless new agricultural land is brought onstream quickly, then I could see F approaching 100% in the short term, for all practical purposes. Massive shifts in agriculture can’t happen quickly.

fwiw a retreat of ice flows exposing land does not equate to “whoopie new farmland and pastures”. Absence of permanent ice cover is only one (obvious) condition that determines whether or not land is potentially agriculturally productive land. Beware one’s assumptions that drought effected land no longer productive will be replaced as if by the magic of a predictable equation. (if that’s what is being suggested by some)

In the Comments section for the Los Angeles Times, one commenter has frequently cited tide gauges at http://tidesandcurrents.noaa.gov/sltrends/sltrends.html as indicating no acceleration in sea level rise. Looking at graphs for individual stations, I indeed do not see any acceleration in sea level rise, both on the West Coast and East Coast of the USA, and in the Western Pacific. How to compare this to the paper by Stefan Rahmstorf et al “Comparing climate projections to observations up to 2011” accessed at http://iopscience.iop.org/1748-9326/7/4/044035/ ?

#252 Thomas O’Reilly. Hell, yes. Agricultural land requires topsoil, and topsoil takes time. The soil uncovered by glaciers is rock dust. The soil uncovered by the burning of Amazon forests is thin and quickly used up.

The long-term stabilization of climate was irrelevant to the dinosaurs who ran out of food within a few years after the Chicxulub meteor strike.

#251-253–Yes, I agree. Richard pointed out some ways back that much of Siberia wasn’t in fact glaciated, which appears to be more or less correct, though perhaps knowledge is a bit spotty there (or perhaps my searching wasn’t persistent enough.)

However, it also appeared from what I could find that most northerly areas in Siberia lack good topsoil anyway. (Just why that is true might be an interesting question. Maybe someone here knows something on that?)

There will certainly be some agricultural growth in southern Siberia, as there will in the Canadian plains. But enough to make up for massive losses (should they eventuate) in the tropics? In the face of the need to *increase* food supply by a factor of 25-30% to account for baked-in population increase? I find that a doubtful proposition, though I admit I’m handwaving here.

#253 thx for the rational agreement.
Let’s not forget that the Chicxulub meteor strike is the only such event that destabilized the global climate. All others were from massive changes in the atmosphere that involved massive increases in CO2 and other GHG concentrations. The geological volcanic forces started that in the past eons, today it’s man-made forces doing the exact same thing, in essence.
Dinosaurs didn’t get a second chance, and I “suspect” neither will Homo Sapiens.

A side note: this anomaly prompted me to contact Cameron Baccario (developer of the Earth map) and suggest that it might be time to extend the SSTA gradient. Currently it’s impossible to visually distinguish between a (mere!) +6°C anomaly and a +12°C anomaly. It’s not obvious what color could come after white (violet? green?), but recalibrating the existing scale seems even more problematic. I vaguely recall that other climate maps have encountered similar problems lately. Is there an accepted methodology for dealing with “gradient creep”?

I think it plays a role, indirectly if not directly. The Syrian Civil War was preceded by four years of drought, and one million people moving into the cities, where Assad failed to take care of their needs.

Uhm, Chuck, I’d take anything I read at that site with at least a hillock of HCL. If there’s any truth to be found there, it’s probably accidental, because it’s otherwise pure crank bait. Under the HAARP(!) link, for example, the top post begins thus:

Climate engineering is a completely runaway juggernaut of total insanity. The planet’s climate system is unraveling by the day as the geoengineers try frantically to control it with ever more desperate and destructive measures (which were a primary cause of the climate disintegration in the first place).

Yeah, they accept AGW (in a manner of speaking), but you probably don’t want to cite them in support of any reality-based argument. At Greg Laden’s place a while back, some of us tried in vain to instill skepticism in a commenter who seemed to take what she read on geoengineeringwatch at face value, and all but accused us of denial 8^}.

Glen: I understand that a warmer planet had more vegetation, extending to the poles, but these are processes occurring over (at least) thousands of years, while the BPL paper addresses drought issues that may occur in the next 50.

RC: Yes, it takes a long time for robust ecosystems to develop, but wind-blown weeds are pretty quick. The wild card, of course, is humanity. We can, and will attempt to “terraform” regions whose ecosystems have been toppled. As to farming, Sidd found DOI:10.1371/journal.pbio.1002167, which says:

“We show that although the global mean number of days above freezing will increase by up to 7% by 2100 under “business as usual” (representative concentration pathway [RCP] 8.5), suitable growing days will actually decrease globally by up to 11% when other climatic variables that limit plant growth are considered (i.e., temperature, water availability, and solar radiation). Areas in Russia, China, and Canada are projected to gain suitable plant growing days, but the rest of the world will experience losses. Notably, tropical areas could lose up to 200 suitable plant growing days per year. These changes will impact most of the world’s terrestrial ecosystems, potentially triggering climate feedbacks. Human populations will also be affected, with up to ~2,100 million of the poorest people in the world (~30% of the world’s population) highly vulnerable to changes in the supply of plant-related goods and services. ”

If they’re right, and our behavior holds to their scenario, then perhaps 11% of our potential worldwide agricultural output (which assumes we farm 100% of the land) is at risk. Advances in genetics or techniques may recover some, most, or more than all of that loss. Assuredly, if that 11% meant life-or-death for significant numbers of humans, say 1% of us, then we’d simply up our share of the total net primary productivity pie. Elephants will go extinct in the wild before people in the area die in scientifically important numbers from persistent hunger.

The plunge in suitable agricultural days in the tropics means we’ll have a choice:

RC: Starving people make willing homesteaders. And if ethnic and political squabbles prevent that, well, we’re watching a preview of the default migration. Lots of people fleeing hunger and violence in hot and getting hotter lands. Perhaps less than 1% die on the trip. Misery, but survival and a new life.

If there’s suitable land and food prices are sky-high, people will fight for the right to plow.

RC: Starving people make willing homesteaders. And if ethnic and political squabbles prevent that, well, we’re watching a preview of the default migration. Lots of people fleeing hunger and violence in hot and getting hotter lands. Perhaps less than 1% die on the trip. Misery, but survival and a new life.

If there’s suitable land and food prices are sky-high, people will fight for the right to plow, either with their hands or their robots. It didn’t take us very long to populate the Great Plains, and that was with barely-industrial technology.

Kevin: In the face of the need to *increase* food supply by a factor of 25-30% to account for baked-in population increase? I find that a doubtful proposition

RC: Our primary discussion is about whether we will avoid a population crash of perhaps 95% by 2100, not whether we’ll be able to continue to increase in numbers. But your point is well taken. I’ve said that I wouldn’t be surprised if hundreds of millions die. Perhaps even enough to prevent an increase in our numbers by 2100 or cause a small decline, but that’s a stretch. We will take any action our clever minds can come up with to prevent such an outcome. The elephants “must” die. I read that Africa has 60% of the world’s arable land. I don’t accept the claim at face value, but obviously there’s lots of potential farmland left in Africa.

I also read that Siberian topsoil has flaws. They’ve also got melting permafrost, mosquitos, swamps, and whatever else. It doesn’t sound like a pleasant place pre-terraforming.

BPL: Yes, Glen, you silly person. Look how welcome refugees from North Africa are being made in Europe. Refugees from Bangladesh in Pakistan. From Syria in Turkey. From Mexico in the United States. The supply of desperate, homeless people make wonderful colonists, and it’s always easy to find countries that will take them in by the millions.

And my primary point is not whether we will be able to continue to increase in numbers, but whether agriculture is going to be fatally stressed over the coming decades. It appears to me that the mortality we are talking about is not going to remaining neatly isolated: people will not ‘go gentle into that good night’, but will ‘rage against the dying of the light.’ A case in point is the Syrian conflict, which was discussed a bit above. It’s been attributed, in a probabilistic way, to anthropogenic climate change, in a PNAS study:

Century-long observed trends in precipitation, temperature, and sea-level pressure, supported by climate model results, strongly suggest that anthropogenic forcing has increased the probability of severe and persistent droughts in this region, and made the occurrence of a 3-year drought as severe as that of 2007−2010 2 to 3 times more likely than by natural variability alone. We conclude that human influences on the climate system are implicated in the current Syrian conflict.

That’s the future writ small, if we don’t shift course.

I agree that pure agricultural deficit isn’t likely to kill us all. But it’ll never be ‘pure’–political and military responses are pretty much assured. That means further environmental degradation, and also degradation of constructive policy responses to the climate crisis. It means economic chaos, which will further boost mortality. The worst case would be more or less complete social collapse–and in a globalized world, that could well be on a global scale. Widespread nuclear exchanges are certainly a possibility.

I don’t think that is what *will* happen, but I certainly think it *could* happen, if we’re really as foolish as Barton thinks we are.

Perhaps anti-climactically, I also want to address a point in your comment @ #264:

…perhaps 11% of our potential worldwide agricultural output (which assumes we farm 100% of the land) is at risk.

I think that’s wrong. You base that on an 11% decrease in global growing days, per sidd’s cited study. But you can’t assume a linear relationship between the two: what is the distribution of the change in growing days? And what is the sensitivity of productivity to that metric? After all, just one ‘unsuitable growing day’ could be enough to kill a crop, if it’s ‘unsuitable’ enough–in which case all subsequent ‘suitable’ days of that growing season become moot.

Certainly, those areas of the tropics–how extensive are they, one wonders?–in which the deficit becomes 200 days are pretty well ‘stuffed’ (to indulge in an ironic play on words.)

Finally, let me say that I had to read your last sentence–“And that’s by 2100, not 2040”–twice. I couldn’t believe that you regard your 3-part ‘choice’ as anything but a catastrophic dilemma–pretty much a ‘Kobayashi Maru’ scenario. (“Transfer much of the tropic’s population to other regions”, forsooth!)

So I posted a link to a questionable site but the question remains… are we seeing a mass exodus from Northern Africa and the Middle East that is primarily due to a changing climate? I think the answer is yes. This appears to be an escalating situation that is putting a lot of stress on Hungary and Italy. I’m sure there are other mitigating factors such as conflict etc.

I guess my real question though… is this just the beginning of climate induced mass migrations? Thoughts?

RC: Not even close, kid. Of course the refugees are unwelcome, but in science, reality counts. The refugees ARE being absorbed regardless of the kicking, screaming, and horrid but statistically-irrelevant deaths. Yep, Trump might get elected and might try to evict undocumented migrants, but I’m pretty sure he’d fail. And even if Trump kicks out latins and Europe kicks out everyone they can, in neither case are REFUGEES threatened, except by misclassification. Refugees are a protected class. (at least so far)

BPL: Right, like we took action to prevent Hitler becoming a major threat to the world.

RC: Of course not. We took action to remove the problem after it manifested. Same way we’ll attempt to handle climate change. It’s how we do things.

Kevin: Syria

RC: Yes, a grand example. Perhaps a 1% death rate and 15% have left the country. Scientifically, a small death rate and a large exodus.

Kevin: I think that’s wrong. You base that on an 11% decrease in global growing days, per sidd’s cited study. But you can’t assume a linear relationship between the two

RC: I totally agree, which is why I said “Perhaps”. It’s a base number which would require lots of work to firm up. For example, shifting a growing day from Kansas to Siberia would decrease soil but increase sunlight. How would that play out? I suspect that the real losses would be higher. However, their raw number seems far more firmed-up than BPL’s number, which consists of an extrapolation and a few non-quantified comments and nary a scientific connection between drought and death count. Was any math involved in coming up with 250 million survivors? In fact, it is impossible to reconcile the two papers. Since BPL’s seems simplistic and was rejected, I’d bet on the other.

Kevin: I couldn’t believe that you regard your 3-part ‘choice’ as anything but a catastrophic dilemma

RC: I’m speaking calmly, but to take your Star Trek analogy in hand, I’m channelling Spock. Yep, hundreds of millions may die, billions might lose everything and almost die, kids might lose huge chunks of neurons for life, fights, wars, maybe even nuclear. Like Kobayashi Maru, reality is what it is, but only if we choose to not swap our reality by adding sulphur to our carbon-based geo-engineering experiment. When the expected damage from a swap is far less than the expected damage from continuing on, then an analysis which doesn’t include the possibility of a swap is incomplete at best. Kirk beat Kobayashi by “geo-engineering” the computer.

Kevin: Apparently you somehow feel such choices are actually workable.

RC: Of course. Assume BPL is 100% right about the science and our reactions. In 2100 we’ve got 250 million people. That’s plenty, and the 8 or so billion deaths become mere history of a somewhat secondary importance. Instead of lamenting the loss of human life, folks will probably say, “Gee, I wish we hadn’t killed off most of the biosphere. I hear fish were cool.”

#272–Well, as usually happens in dialogue where there is some measure of attention and good faith between parties, we’ve narrowed our differences: now we’re down to “an unbelievably horrible future which doesn’t quite kill off all humans” versus “an unbelievably horrible future which still might.”

I suppose I should feel rather more cheerful about that than I do.

And I can’t forbear to remark that I suspect that in any future in which all the various classes of organisms belonging to the paraphyletic group we call ‘fish’ were extinct, the human impact would be rather greater than an attack of nostalgia.

whether agriculture is going to be fatally stressed over the coming decades….

One of my old friends has been working for decades to replace corn and soybeans with woody agriculture — tree/bush nuts, maturing at the same time so fields can be mechanically harvested using a modified blueberry-picker that shakes the nuts out. It’s working. No plowing, fields full of wildlife, better use of available sunlight hours through the year to produce food, building topsoil, surviving extreme weather, no months of bare fields eroding between plowings every year.

He quoted one of our college’s biologists as saying “Damn you — because you’re giving me hope.”

I see little or no reason to worry about climate change. Mr. Obama is giving powerful speeches about the dangers, so change is happening. If things were really serious, scientists would be raising a strong alarm to help our species make needed changes.

Human beings have a powerful history of recognizing the error of our ways and correcting. That is how we managed to avoid the actual extinction of a species like the passenger pigeon and allow it to make a comeback as a fixture in our beautiful cities. I have little doubt that when a lot of species are facing extinction as the passenger pigeon once did, the human beings of the planet will respond appropriately and act to save the world. The US will lead the way.

We may need to build border walls first, but once we have addressed the illegal immigration crisis, I have no doubt that we will address this pesky climate issue.

Is this anything like, “Nobody saw it [crash] coming,” in which any number of people did? Much like you say “anyone” above when quite a few have seen high SLR this century for a while now. I’m sure you mean hardly anyone; just checking.

I see R.C. is up to his old habits. Not going to give up on the geoengineering meme. In the mean time I’m watching the evening news and the big story is Climate Change. Alaska and the massive migration of people fleeing from Northern Africa and the Middle East. I hope the folks at Real Climate will address this situation and provide a little insight into where all this may be headed. The President is taking major steps in the right direction while still allowing Shell Oil to extend their permits to drill in the Arctic. Is this an example of cognitive dissonance?